From minnows to deep-water whoppers, researchers are conducting the first comprehensive fish survey in more than 30 years as part of a multi-million dollar effort to determine the lake’s health.

Studying the food web, from zooplankton to lake trout lunkers, is one way of understanding water quality and negative stressors such as road salt, nutrients and invasive species that impact it.

“We’re trying to find out who’s here, where they are, how many there are and if so, how and why they’re changing,” said Rick Relyea, Jefferson Project director.

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The project, launched two years ago, is a long-term collaboration between Rensselaer Polytechnic Institute, IBM and the Fund for Lake George. The high-tech initiative has already attracted attention from international parties, such as the Latin American Nature Conservancy, and is expected to eventually have applications in water bodies around the world.

Hintz, a University of Southern Illinois post-doctorate research associate, is leading the fish survey.

Since spring, his team has collected samples of many different species using a variety of nets -- some placed in the water and left overnight, along with larger ones that require hands-on work.

“We have to approach it in several different ways,” Hintz said.

The program is also relying on help from local fishing groups and the state Department of Conservation’s angler diary program to gather statistical data about the types of fish caught in Lake George.

In addition, on Monday, another sophisticated piece of equipment called CPICS (Continuous Plankton Imaging and Classification Sensor) joined the effort. A camera mounted on this underwater device takes six images per second, thousands each day, of tiny organisms that smaller fish feed on.

“This identifies in milliseconds what’s there instead of having to take water samples and look for organisms under a microscope,” Relyea said. “The computers doing this are brand new.”

The Fish and food web survey is just one part of this year’s Jefferson Project work. There are three more main elements that the project will cover – sediment core sampling that tells the lake’s biological history; cyber-infrastruture; giving data-collection instruments the ability to communicate and make decisions about the presence of potentially harmful elements in the water. They’ll also fill large tanks filled with Lake George water have been set up at RPI in Troy where researchers can study, for example, the consequences of increased road salt levels in the lake.

All of these elements are interconnected. Salt, for example, might affect plankton levels that small fish feed on, which are prey for larger fish. More than 90 percent of the fish captured are released. Some are dissected to see what they’re eating.

The size and weight of all fish are recorded. Such information will be tracked over several years to see if fish are losing weight in relation to their length, which could indicate the presence of a harmful lake impact.

“Fat fish are good because everyone wants to catch a big fish,” Hintz said.